Investigative Study for NSS Chemistry Curriculum

1. Investigative Study for NSS Chemistry Curriculum Mr W C HO 10 June 2006

2. Investigative Study • Provide students with opportunities to design and conduct an investigation with a view to solving an authentic problem • Students will learn about scientific processes and how these processes work to generate new information

3. What is Scientific Inquiry? • “Scientific inquiry refers to the diverse ways in which scientists study the natural world and propose explanations based on the evidence derived from their work” National Science Education Standards Michael Faraday(1791-1867)

4. A Definition of Science as Inquiry “Student inquiry is a multifaceted activity that involves making observations; posing questions; examining books and other sources of information to see what is already known; planning investigations; using tools to gather, analyze and interpret data; reviewing what is already known in light of the student's experimental evidence; proposing answers, explanation, and predictions; and communicating the results. Inquiry requires of assumptions, use of critical and logical thinking, and consideration of alternative explanations.” “As a result of participating in inquiries, students will increase their understanding of the science subject matter investigated, gain an understanding of how scientists study the nature world, develop the ability to conduct investigations, and develop the habits of mind associated with science.” (Beyers, 2001)

5. Experiences • S4-5 – For revision of topics • S6 – 2 TAS experiments • Chemistry Olympiad – scale it down, of course! For development of topics for investigative study

6. Development Stage 1 • Task group to develop and tryout exemplar materials • Small scale investigations that could be completed within 4-5 periods, i.e. 2 periods for planning, discussion and drafting of proposal (pre-lesson information search and planning might be required) and 2-3 periods for carrying out • Investigations: Chemical Cells, Carbonate Rocket, Extraction of copper, Useful products from waste materials

7. Making more money for the company and get a bonus #1

8. Making more money for the company and get a bonus #2 • Worksheets, S4 students • Possible approaches (no unique answer, but only a “best” answer in solving problems in science) • Prior knowledge: acids and bases, displacement reaction, mole concepts • Students’ work: didn’t divide sample into smaller portions for trial; deciding amount of chemicals used; problem in removing impurities/excess reagents; measuring the mass of product

9. Group 1: Displacement with zinc powder Proposal Report

10. Group 1: Displacement with zinc powder

11. Group 1: Displacement with zinc powder Peer Learning

12. Group 2: Displacement using Mg

13. Group 3: Carbon Reduction

14. Making more money for the company and get a bonus #3 • Assessment

15. Acids and Bases • Compare the acidity / alkalinity of two household items e.g. indigestion tablets, vinegar, softdrinks, cleansing agent, lemon tea, soap • Review the techniques in carrying out titration • Proposal form (topic for investigation, objective, reason for carrying out the investigation, prediction and its reason behind, variables to be investigated and controlled, etc; example given) • Reflect students’ • understanding of the relevant concepts e.g. conc vs strength, indicators • Laboratory skills • Titration / Microscale titration • Peer and self-assessment

16. Useful products from waste (TAS project) • 過期食物經常被視為無用的廢物，但在社會富庶的香港處理過期食物為一重要的問題。作一個社會公民及一位學化學的學生，你能作出甚麼貢獻呢？ 從柚子內皮提取果膠製作天然爽膚水 檸檬油 利用脫脂牛奶及純牛奶製造膠水 從食物中提取螢光物質 以回鍋油製作環保香皂

17. Analysis of Vitamin C in Fruit Juices – “Perhaps the most frequently performed investigation in HK” • S6 TAS projects • Case 1 • 17/4 ws#1 • 5/5 ws#2 • 2 expt sessions • 15/5 lab report • 22/5 ~ 10 min group presentation • ~2 students / group • Assess Ability Areas A and B • Case 2 • ~4 students / group, distribution of work and reflections, 4 yrs experience • Challenges to students • Using direct or back titration • Deciding the amount/conc. of chemicals used • Explaining the discrepancies between the expt values (5-150 mg / 100 cm3) with those displayed on the juice label

18. Distribution of work

19. Assessing group work • Collaboration: encourage students to share tasks in groups, pool their gathered information, to brainstorm, to listen, to criticize positively and to accept criticism as being constructive • Differential contributions made by group members • Difficult of arriving at a fair mark for individuals; narrow bands of marks • (1) – Student adopt different roles within the group; assessment focus on how well each student performed her different role • (2) – every student may be expected to contribute equally to all aspects; each criterion applied equally to each student

20. Assessment of Contribution to Group • Student ______________ has contribute to the group’s work in the following ways: • The average rating for each individual is then deducted from the group mark and allocated to that individual as her mark. Habeshaw, S & Gibbs, G & Habehaw, T (1998) Interesting ways to assess your students

21. Student Self-assessment Forster, M & Master, G (1996) Projects Assessment Resource Kit

22. Logistics • When to implement IS? • How to use the allocated lesson time of 20 hours? • Extended period of time (5-7 weeks; 4-5 periods/week) or in one go (3 days; 6 hrs/day)? • Holidays or post exam? • Considerations: prior knowledge, students’ motivation and ability, time for quality interaction (thinking and working)

23. Investigative Study • Searching and defining questions for investigation (~3 hrs) • Developing an investigation plan (~4 hrs) • Conducting the investigation (6 hrs) • Organising and analysing data for a justified conclusion (~4 hrs) • Presenting findings with written reports, posters and other means (~3 hrs)

24. Using the Allocated Lesson Time (20 hrs) Double period (2 x 40 mins ~1.3 hr); 2.67 hrs /week; 7.5 weeks

25. Development Stage 2 Full-scale Tryout Schedule White – S5 students; green – Snacks, S4 students; blue – Indicators, S6 students; red – Self-heating can, S6 students

26. Use of IT • Facilitate students’ collaboration and keep some record the learning process

27. Information to be collected • Students’ proposals • Messages in discussion forum • Photos and Video • Project reports, ppt, posters, etc • Students’ self and peer assessment record • Teacher’s assessment criteria and marks • Students’ comments (through a questionnaire) • Teachers’ and LT’s comments and suggestions • Modified student handouts, forms, etc

28. Choosing a topic • Activities that are authentic, motivating, meaningful, simple, inexpensive, appropriate, feasible, relevant, safe and fun • Types of investigations • Quantitative determination • Extraction of a substance and testing its properties / uses • Construction and testing a device • Using ‘established’ methodology on new topic • Applying ‘new’ methodology to established topic

29. Appropriateness of the Topic • Does the activity address something worth learning? • Is the topic socially relevant, interesting and motivating? • Is the cognitive demand appropriate? • Do students have the required prior knowledge and adequate skills? • Are resources such as journal articles, reference books, chemicals and apparatus available? • Is the time available sufficient for the activity? • Can laboratory technicians and others help in its implementation?

30. E1: Which snack is healthier? • Amount of fat and degree of unsaturation • Salt content (assume amount of Cl- equal to Na+) • Most packages with no nutrition information • Gravimetric method, AgCl(s) or • Titrimetric methods • Volhard method: back titration of Ag+ with KSCN using Fe2+ as indicator • Mohr method: titration with Ag+ using K2CrO4 as indicator

31. Currie yellow (acidic), orange/red (alkaline)

32. E2: Acid-base Indicators • Cabbages of the same species have two different colours, Why? • Can plant pigments be used as indicators for acid-base titration? • Red cabbage, blackberries, hibiscus flowers, grape skin, mangosteen (山竹果), dragon fruit (火龍果), Ribena

33. E2: Acid-base Indicators • Black bean (boiled with water); red (acidic); dark green (alkaline) • Curry powder (dissolved in alcohol); • Can the solutions be used as indicators for titration between strong acid and weak alkalis? • How about the titration for weak acid and strong alkalis? • Compare results with common indicators • Titration curve • pH meter / tester, datalogger

34. E3: Self-heating Can

35. E3: Self-heating Can

36. 消委會形容 「夾一箸菜乾（約17條金針菜），二氧化硫含量已超出常人一日最高攝取量」，建議市民煮食前應徹底浸泡及洗。

37. List of possible topics: T1

38. Adjusting the learning tasks for students with different abilities • Vary the scale, nature and demand of learning tasks for students of differing abilities. • With students who are less able, small and less demanding tasks can help them to build up their capacity and confidence gradually. Teacher may break down a complicated investigation into a series of simple ones. • For capable students, teachers have to design tasks which are challenging enough to maintain their motivation. A scientific investigation can be made more demanding by building on more background knowledge, including more variables, collecting more data, or adopting more sophisticated instrumentation and skills.

39. Assessment • Design • Process • Report

40. Students’ Reflection 1

41. Students’ Reflection 2

42. Students’ Reflection 3

43. Acknowledgement Dr Yeung Lam Lung, HK University of Science & Technology Mr Chan Kam Yuen, TWGH Mrs Wu York Yu Mem College Mr Hui Man Tuen, St Mark's School Ms Leung Siu Wai, Ho Fung College Ms Liu Mei Po, True Light Middle School (Kln) Mr Pun Kwong Cheung, SKH Tsang Siu Tim Sec Sch Mr Ng Ben, TWGH Chang Ming Thien College Mr Ng Kai Bun, Fukien Secondary School (Siu Sai Wan) Mr Poon Chan Kwok, Cheung Sha Wan Catholic Sec Sch Ms Lam Siu Yan, St Paul’s Convent School Ms Joyce Hui, PAOC Ka Chi Secondary School Ms Soo May Kei, Wellington Ed Org Chang Pui Chung Mem Sch Mr Cheng Kin Tak, United Christian College (Kowloon East) Mr Chan Wai Fat, Wa Ying College Mr Chan Chi Shing, YOT Chan Wong Suk Fong Mem Sec Sch Mr Wong Wing Chuen, CCC Mong Man Wai College

44. ChemISTry http://is.myftp.org cdosc21@edb.gov.hk Tel. 3698 3438